今天在翻看Oreilly 出版的 Developing.Large.Web.Applications 一书时,瞅见了RDFa这个东东。RDFa Resource Description Framework with Attributes,它定义了一种标准的方式来注解信息,扩展HTML以提供更多的含义。

RDFa 基本上都是关于主题Subject、断言 Predicate、对象 Object 的陈述。

主题描述了要讨论的内容,断言是声明定义的关系,对象是由主题形成关系的资源。

通过HTML 的属性标签来组成这样一个三元组。参看已经定义的一些属性。

 

XHTML中与RDFa有关的属性

rel A predicate URI used for expressing a relationship between two resources.

rev A predicate URI used for expressing a relationship between two resources in reverse.

content An object literal used for supplying machine-readable content for a literal.

href An object URI used for expressing the partner resource of a relationship.

src A URI object used for expressing the partner resource of a relationship when the resource is embedded (e.g., an

p_w_picpath).


RDFa特有的属性

about A URI subject used for expressing what the data is about. By default, the base URI for the document is the root

URI for all statements.

property A URI predicate used for expressing a relationship between the subject and some literal text.

resource A URI object used to express a resource that is not visible in the document.

datatype A URI for expressing a literal’s datatype. The datatype is defined as part of a vocabulary.

typeof A URI for expressing the type of a subject. The type is defined as part of a vocabulary.

 

参考

蓝色理想 http://www.blueidea.com/tech/web/2009/7015.asp

IBM http://www.ibm.com/developerworks/cn/xml/x-matters37.html